{"id":138138,"date":"2021-03-31T03:00:30","date_gmt":"2021-03-31T13:00:30","guid":{"rendered":"https:\/\/www.hawaii.edu\/news\/?p=138138"},"modified":"2021-03-31T08:03:46","modified_gmt":"2021-03-31T18:03:46","slug":"first-images-of-freshwater-plumes-at-sea","status":"publish","type":"post","link":"https:\/\/www.hawaii.edu\/news\/2021\/03\/31\/first-images-of-freshwater-plumes-at-sea\/","title":{"rendered":"Scientific breakthrough: First images of freshwater plumes at sea"},"content":{"rendered":"<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading time: <\/span> <span class=\"rt-time\"> 3<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span><div class=\"responsive-video-wrap-post\"><figure class=\"wp-block-embed wp-block-embed-youtube is-type-video is-provider-youtube epyt-figure\"><div class=\"wp-block-embed__wrapper\"><div class=\"epyt-video-wrapper\"><iframe  id=\"_ytid_50724\"  width=\"676\" height=\"676\"  data-origwidth=\"676\" data-origheight=\"676\" src=\"https:\/\/www.youtube.com\/embed\/FstezZydlJk?enablejsapi=1&origin=https:\/\/www.hawaii.edu&rel=0&autoplay=0&cc_load_policy=0&cc_lang_pref=&iv_load_policy=1&loop=0&fs=1&playsinline=0&autohide=2&theme=dark&color=red&controls=1&disablekb=0&\" class=\"__youtube_prefs__  no-lazyload\" title=\"Scientific breakthrough: First images of freshwater plumes at sea\"  allow=\"fullscreen; accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen data-no-lazy=\"1\" data-skipgform_ajax_framebjll=\"\"><\/iframe><\/div><\/div><\/figure><\/div>\n<p>The first imaging of substantial freshwater plumes west of <span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span> Island may help water planners to optimize sustainable yields and aquifer storage calculations. University of <span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span> at M\u0101noa researchers demonstrated a new method to detect freshwater plumes between the seafloor and ocean surface in a study recently published in <em><a href=\"https:\/\/agupubs.onlinelibrary.wiley.com\/doi\/10.1029\/2020GL091249\">Geophysical Research Letters<\/a><\/em>.<\/p>\n<p>The research, supported by the <a href=\"https:\/\/www.hawaii.edu\/epscor\/ike-wai-project\/\"><span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span> <abbr>EPSCoR<\/abbr> &#699;Ike Wai project<\/a>, is the first to demonstrate that surface-towed marine controlled-source electromagnetic (<abbr>CSEM<\/abbr>) imaging can be used to map oceanic freshwater plumes in high-resolution. It is an extension of the <a href=\"https:\/\/www.hawaii.edu\/news\/2020\/11\/25\/offshore-freshwater-discovery\/\">groundbreaking discovery of freshwater beneath the seafloor<\/a> in 2020. Both are important findings in a world facing climate change, where freshwater is vital for preserving public health, agricultural yields, economic strategies, and ecosystem functions.<\/p>\n<h2>Profound implications<\/h2>\n<figure id=\"attachment_138149\" aria-describedby=\"caption-attachment-138149\" style=\"width: 300px\" class=\"wp-caption alignright\"><a href=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2021\/03\/manoa-ike-wai-fresh-water.png\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2021\/03\/manoa-ike-wai-fresh-water-300x169.png\" alt=\"Conceptual illustration showing freshwater plumes at sea\" width=\"300\" height=\"169\" class=\"size-medium wp-image-138149\" srcset=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2021\/03\/manoa-ike-wai-fresh-water-300x169.png 300w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2021\/03\/manoa-ike-wai-fresh-water-130x73.png 130w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2021\/03\/manoa-ike-wai-fresh-water.png 676w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-138149\" class=\"wp-caption-text\">Conceptual illustration showing freshwater plumes at sea (click\/tap for larger image)<\/figcaption><\/figure>\n<p>While the <abbr>CSEM<\/abbr> method has been used to detect the presence of resistive targets such as oil, gas and freshwater beneath the seafloor, this study is the first time <abbr>CSEM<\/abbr> was applied to image freshwater in the ocean water column, according to &#699;Ike Wai research affiliate faculty <strong>Eric Attias<\/strong>, who led the study.<\/p>\n<p>&ldquo;This study has profound implications for oceanography, hydrogeology and ocean processes that affect biogeochemical cycles in coastal waters worldwide,&rdquo; said Attias. &ldquo;Using <abbr>CSEM<\/abbr>, we now can estimate the volumes of freshwater emanating to the water column. This is indicative of the renewability of <span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span>\u2019s submarine freshwater system.&rdquo;<\/p>\n<p>Submarine groundwater discharge (<abbr>SGD<\/abbr>), the leaking of groundwater from a coastal aquifer into the ocean, is a key process, providing a water source for people, and supporting sea life such as fish and algae. According to <abbr title=\"University of Hawaii\">UH<\/abbr> M\u0101noa <a href=\"http:\/\/www.soest.hawaii.edu\/earthsciences\/\">Department of Earth Sciences<\/a> Associate Professor and study co-author <strong>Henrietta Dulai<\/strong>, the location of offshore springs is extremely hard to predict because of the unknown underlying geology and groundwater conduits.<\/p>\n<p>&ldquo;The flux of such high volumes of nutrient-rich, low salinity groundwater to the ocean has great significance for chemical budgets and providing nutrients for offshore food webs,&rdquo; said Dulai. &ldquo;It is great to have a method that can pinpoint discharge locations and plumes as it opens up new opportunities to sample and identify the age of the water, its origin, chemical composition, and its significance for marine ecosystems in this otherwise oligotrophic (relatively low in plant nutrients and containing abundant oxygen in the deeper parts) ocean.&rdquo;<\/p>\n<h2>Four Olympic swimming pools<\/h2>\n<figure id=\"attachment_131295\" aria-describedby=\"caption-attachment-131295\" style=\"width: 300px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2020\/11\/manoa-soest-freshwater-attias-300x169.jpg\" alt=\"Eric Attias deploys CSEM system\" width=\"300\" height=\"169\" class=\"size-medium wp-image-131295\" srcset=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2020\/11\/manoa-soest-freshwater-attias-300x169.jpg 300w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2020\/11\/manoa-soest-freshwater-attias-130x73.jpg 130w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2020\/11\/manoa-soest-freshwater-attias.jpg 676w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><figcaption id=\"caption-attachment-131295\" class=\"wp-caption-text\">Deploying the <abbr>CSEM<\/abbr> system<\/figcaption><\/figure>\n<p>This study included electromagnetic data driven 2D <abbr>CSEM<\/abbr> inversion, resistivity-to-salinity calculation, and freshwater plume volumetric estimation. Through the use of <abbr>CSEM<\/abbr>, the research team was able to image surface freshwater bodies and multiple large-scale freshwater plumes that contained up to 87% freshwater offshore <span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span> Island. The results imply that at the study site substantial volumes of freshwater are present in the area between the seafloor and the ocean\u2019s surface.  A conservative estimate for one of the plumes suggests 10,720 cubic meters or approximately the volume of four Olympic-sized swimming pools.<\/p>\n<p>The methodology used in this study can be applied to coastal areas worldwide, thus improving future hydrogeological models by incorporating offshore <abbr>SGD<\/abbr> and optimizing sustainable yields and storage calculations. Attias plans to extend the novel use of <abbr>CSEM<\/abbr> to further prove its application in imaging freshwater at other volcanic islands around the globe.<\/p>\n<p>Attias will present his work at the <a href=\"http:\/\/www.hawaii.edu\/epscor\/international-tropical-islands-water-conference\/\">International Tropical Island Water Conference<\/a> taking place April 12&#8211;15, 2021. Hosted by the <a href=\"https:\/\/www.wrrc.hawaii.edu\"><abbr>UH<\/abbr> Water Resources Research Center<\/a> and <span aria-label=\"Hawaii\">Â鶹´«Ã½<\/span> EPSCoR, this conference brings together water scientists, water managers and community members from around the world to share cutting-edge research and learn from each other\u2019s experiences managing and understanding water resources across a broad range of tropical island settings.<\/p>\n<p>This project is supported by the National Science Foundation <abbr>EPSCoR<\/abbr> Program Award <abbr>OIA<\/abbr> #1557349.<\/p>\n<p>This work is an example of <abbr>UH<\/abbr> M\u0101noa\u2019s goal of <a href=\"https:\/\/manoa.hawaii.edu\/wp\/wp-content\/uploads\/2020\/12\/manoa-2025-strategic-plan.pdf#page=25\">Excellence in Research: Advancing the Research and Creative Work Enterprise<\/a> (<span class=\"small-text\"><abbr title=\"Portable Document Format\">PDF<\/abbr><\/span>), one of four goals identified in the <a href=\"https:\/\/manoa.hawaii.edu\/wp\/wp-content\/uploads\/2020\/12\/manoa-2025-strategic-plan.pdf\">2015&#8211;25 Â鶹´«Ã½<\/a> (<span class=\"small-text\"><abbr title=\"Portable Document Format\">PDF<\/abbr><\/span>), updated in December 2020.<\/p>\n<p>&#8212;By Maria Dumanlang<\/p>\n<div class=\"responsive-video-wrap-post\"><figure class=\"wp-block-embed wp-block-embed-youtube is-type-video is-provider-youtube epyt-figure\"><div class=\"wp-block-embed__wrapper\"><div class=\"epyt-video-wrapper\"><iframe  id=\"_ytid_26449\"  width=\"620\" height=\"349\"  data-origwidth=\"620\" data-origheight=\"349\" src=\"https:\/\/www.youtube.com\/embed\/D0rqJXhgWas?enablejsapi=1&origin=https:\/\/www.hawaii.edu&rel=0&autoplay=0&cc_load_policy=0&cc_lang_pref=&iv_load_policy=1&loop=0&fs=1&playsinline=0&autohide=2&theme=dark&color=red&controls=1&disablekb=0&\" class=\"__youtube_prefs__  no-lazyload\" title=\"\u2018Ike Wai Project \u2013 Electromagnetic imaging of large-scale freshwater plumes offshore Hawai&#039;i\"  allow=\"fullscreen; accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen data-no-lazy=\"1\" data-skipgform_ajax_framebjll=\"\"><\/iframe><\/div><\/div><\/figure><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Researchers demonstrated a new method to detect freshwater plumes between the seafloor and ocean surface.<\/p>\n","protected":false},"author":16,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30,12],"tags":[521,1467,1363,107,9,56,1043,347],"class_list":["post-138138","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research","category-video","tag-epscor","tag-manoa-excellence-in-research","tag-manoa-research","tag-oceanography","tag-uh-manoa","tag-video-2","tag-water","tag-water-resources-research-center","entry","has-media"],"aioseo_notices":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/138138","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/comments?post=138138"}],"version-history":[{"count":8,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/138138\/revisions"}],"predecessor-version":[{"id":138343,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/138138\/revisions\/138343"}],"wp:attachment":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/media?parent=138138"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/categories?post=138138"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/tags?post=138138"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}